In the industrial field, the assembling of mating members has a wide variety of applications. A typical example thereof is mechanical parts requiring a fit such as a clearance fit or an interference fit. As an example of clearance fit, there can be cited many examples including upper and lower punches and a sleeve in a press molding die, which is an assembly in which the members can be moved relatively, a rolling element and inner and outer rings in a rolling bearing, a piston and a cylinder liner in an internal combustion engine, and a piston pin and a piston and a connecting rod.
Also, as an assembly in which members requiring a fit such as a transition fit or an interference fit cannot be moved relatively, there can be cited fixing of a boss to a rim in a gear, fitting of a bearing bush in a housing, and fastening of a ceramic rotor shaft portion to a metallic shaft in a ceramic gas turbine rotor. In the case where such members are connected, the relative dimensions in the connecting portion is important.
The shape dimension of a member distributes with a variation. In fitting, in order to meet a proper fitting condition, the variations in shape dimension of member are decreased by machining, that is, a member is machined so as to have high accuracy. However, in some cases, sufficient machining accuracy cannot be secured, or machining cannot be performed. In such cases, conventionally, a method has been used in which the shape dimension of member is measured individually, and members are classified according to dimension range based on the measurement result to form some dimension range lots.
After the mating members are classified into some dimension range lots as described above, proper mating dimension range lots are selected, and members in each lot are used to make assembly. Sometimes, the dimension range lot classification is made for both members. Sometimes, the classification is made for only a member having relatively large variations because it cannot have sufficient machining accuracy or cannot be machined, and the shape dimension of the mating member is matched to a typical dimension of the dimension range lot.
In this method, however, since the influence of dimensional variations in a dimension range lot cannot be averted, it cannot be said that a sufficiently proper fitting condition can be realized. Therefore, a method has been thought in which based on the dimensional data inherent in individual member, processing is performed such that the mating members are machined individually so as to have a dimension that meets a proper fitting condition, or members having such a dimension are selected, by which a combination having a proper fitting condition is realized.
Conventionally as well, for example, a method has been used in which the dimensional data of individual members are entered on a measurement recording sheet, a number or any identification symbol is put on the members, and based on the dimensional data on the recording sheet, the mating members are subjected to the aforementioned processing.
However, in the method in which the dimensional data of individual members are entered on a measurement recording sheet minutely to control the members as described above, as the number of members increases, the work for entering data on the recording sheet becomes troublesome, and also the work for reading the data on the recording sheet becomes troublesome, which poses a problem in that not only enormously much time is required for the entering and reading work but also errors in entering and reading occur frequently.
The error in reading is thought to be basically caused by the fact that the member itself and the data are handled separately. Especially when a large quantity of members are moved to a place distant from the place where the members have been processed and are combined with the mating member, the member and information are transferred with a message not being delivered satisfactorily from worker to worker, which makes the problem more remarkable.
The present invention has been made in view of the above situation, and accordingly an object thereof is to provide a method in which an individual member and inherent information regarding the dimension etc. of the member can be handled integrally, when the mating members are combined with each other, members having a dimension that meets a proper combining condition are selected, and when the member is processed so as to correspond to the property thereof, proper processing corresponding to the inherent property of each member can be performed easily and surely without troublesome work.